How precipitation and grazing influence the ecological functions of drought-prone grasslands on the northern slopes of the Tianshan Mountains, China?

Abstract

Drought-prone grasslands provide a critical resource for the millions of people who are dependent on livestock for food security. However, this ecosystem is potentially vulnerable to climate change (e.g., precipitation) and human activity (e.g., grazing). Despite this, the influences of precipitation and grazing on ecological functions of drought-prone grasslands in the Tianshan Mountains remain relatively unexplored. Therefore, we conducted a systematic field investigation and a clipping experiment (simulating different intensities of grazing) in a drought-prone grassland on the northern slopes of the Tianshan Mountains in China to examine the influences of precipitation and grazing on aboveground biomass (AGB), soil volumetric water content (SVWC), and precipitation use efficiency (PUE) during the period of 2014-2017. We obtained the meteorological and SVWC data using an HL20 Bowen ratio system and a PR2 soil profile hydrometer, respectively. We found that AGB was clearly affected by both the amount and seasonal pattern of precipitation, and that PUE may be relatively low in years with either low or excessive precipitation. The PUE values were generally higher in the rapid growing season (April-July) than in the entire growing season (April-October). Overall, moderate grazing can promote plant growth under water stress conditions. The SVWC value was higher in the clipped plots than in the unclipped plots in the rapid growing season (April-July), but it was lower in the clipped plots than in the unclipped plots in the slow growing season (August-October). Our findings can enhance the understanding of the ecological effects of precipitation and grazing in drought-prone grasslands and provide data that will support the effective local grassland management.

Spatiotemporal Evolution of Mountainous Ecosystem Services in an Arid Region and Its Influencing Factors: A Case Study of the Tianshan Mountains in Xinjiang

“…Usually, an increase in PD or GDP will impose pressure on the ecosystem [36], which may reduce ecological space, threaten biodiversity, and thereby hinder the supply of ESs [37,38]. Additionally, grazing is the main disturbance to mountainous ecosystems in arid regions, while overgrazing can cause grassland degradation and adversely affect ecosystem functions [39,40]. It is possible to use grazing intensity (GI) to characterize the disturbance level of grazing activities.…”

“…Large-area grasslands in the Tianshan Mountains are used as pasturelands, so grazing constitutes the primary anthropogenic disturbance to these ecosystems. Moderate grazing can promote plant growth under waterstress conditions [39], whereas overgrazing will lead to the degradation of grasslands and shrubs [22,40], posing a great challenge to the restoration of mountainous ecosystems. At this point, grassland grazing patterns should be improved to maintain a reasonable grazing capacity and reduce the impact of grazing on the ESs provided by mountainous grasslands.…”

Evaluation of ERA5 and ERA5-Land Reanalysis Precipitation Data with Rain Gauge Observations in Greece

“…Reliable and accurate precipitation information is essential for water resources and ecosystem management [1][2][3]. However, there are different data sources to obtain precipitation time-series: (i) ground observations, (ii) satellite estimates, and (iii) numerical simulations [4].…”

The Impact of China’s Grassland Ecological Compensation Policy on the Income Gap between Herder Households? A Case Study from a Typical Pilot Area

“…However, China's grasslands have been seriously degraded in recent years. Relevant studies have shown that human activities, such as overgrazing, are among the main driving forces leading to grassland degradation [11][12][13][14]. To prevent the continued destruction of the grassland ecological environment by human activities, the Chinese government implemented the policy of subsidies and rewards for grassland ecological protection (PSRGEP) in 2011.…”